This invention relates generally to the field of electrical connectors and more particularly to an electrical connector having a shorting member.
In some applications, it is necessary to short a circuit when electrical connectors establishing the primary circuit are disconnected. One such application is a current monitoring circuit which uses current transformers to detect and monitor current in a load line. Typical current transformers include wire wrapped in a coil around a donut-shaped core. The current transformer is installed so that a load line runs through the middle opening of the core. A primary current in the load line induces a secondary current of proportional value in the wire of the current transformer. In typical current monitoring circuits, the secondary current runs through secondary lead lines from the current transformer to a terminal block. A current monitoring device such as an ammeter is connected to the corresponding terminals on the terminal block to accept the secondary current from the secondary lead lines of the current transformer. When the primary current passes through the load line, the secondary current is simultaneously induced in the current transformer and carried by the secondary lead lines to the terminal block. The secondary current then passes from the terminal block to the current monitoring device.
The current monitoring device will from time to time need to be disconnected from the current monitoring circuit. If the current monitoring device is disconnected from the terminal block while primary current is present in the load line, the current transformer will be xe2x80x9copen circuitedxe2x80x9d. When open circuited, the current transformer begins to store energy. Reconnection of the current monitoring device to the current transformer can result in a very large instantaneous current which burns up the current transformer.
In existing current transformer circuits, before disconnecting the current monitoring device from the current transformer, shorting wires or jumpers are required to be installed to prevent open circuiting of the current transformer and the resulting damage. The installation of a jumper across the secondary lead terminals is a cumbersome and time-consuming process requiring the services of a trained technician or professional electrician. Before the current monitoring device is disconnected, the jumper must be installed in the terminal block to electrically connect the two secondary leads and prevent open circuiting of the current transformer. By shorting the two secondary leads before disconnecting the current monitor device, the storage of electrical energy in the current transformer is prevented.
Existing electrical connectors that perform a shorting function upon disengagement of the contacts are inadequate for many types of circuits. For example, it is frequently advantageous for a single electrical connector to house the contacts for multiple electrical circuits. This arrangement requires a single shorting device housed in the connector that is capable of shorting multiple contacts. To accommodate high voltage circuits, electrical connectors require large xe2x80x9cclearance distancesxe2x80x9d or large xe2x80x9ccreepage distancesxe2x80x9d between the shorting member and the contacts. Clearance distance is the straight line distance between electrical conductors when an open space is between the conductors. Creepage distance is the path measured between electrical conductors when there is a non-conductive surface between the conductors. Because of the inadequate clearance or creepage distance between shorting members and the contacts of the connector, existing electrical connectors are limited to use on low voltage applications.
Among the several objects and features of the present invention may be noted the provision of an electrical connector capable of shorting a circuit when disconnected from a mating connector; the provision of such an electrical connector which can short three or more different contacts of the connector; the provision of such an electrical connector which can short either male or female contacts; the provision of such an electrical connector which can short non-adjacent contacts; the provision of such an electrical connector which can fully disengage the shorting member; the provision of such an electrical connector useful in circuits carrying larger voltages; the provision of such an electrical connector which can use either fixed or removable contacts; the provision of such an electrical connector which can provide simple variations of function that are easily incorporated into manufacture.
Generally, the electrical connector of the present invention comprises a first insulating body with at least three first contacts housed in the first insulating body. A second insulating body houses at least three second contacts. The first and second contacts are adapted for interengagement to produce an electrical connection. A shorting member is mounted on the first insulating body and is disposed for electrically connecting the first contacts. When the first and second contacts are not interengaged, the shorting member connects the first contacts in an engaged position for simultaneously electrically shorting the first contacts.
In another aspect of the present invention, the electrical connector of the present invention generally comprises an insulating shroud that surrounds each of the second contacts. Each insulating shroud is sized and shaped to engage the shorting member as the first and second insulating bodies are moved to interengage the first and second contacts. The insulating shroud moves the shorting member to a disengaged position in which the shorting member is disengaged from at least some of the first contacts.
In another aspect of the present invention, an electrical shorting member for connecting multiple contacts of an electrical connector assembly is provided. The electrical shorting member comprises a web having a first pair of arms and second pair of arms. The first pair of arms is connected to the web and arranged for simultaneously engaging one of the multiple contacts. The second pair of arms is connected to the web at a location spaced apart from the first pair of arms. The second pair of arms is arranged for simultaneously engaging another one of the multiple contacts so that the first and second arms are adapted to engage respective multiple contacts to provide a shorting connection by way of the web between the contacts of the electrical connector assembly.
In yet another aspect of the present invention, an electrical connector assembly generally comprises a first insulating body formed for receiving at least three first contacts therein, and a second insulating body formed for receiving at least three second contacts therein. The second insulating body is adapted for connection with the first insulating body. A shorting member is mounted on said first body and disposed for engaging said first contacts upon insertion of said first contacts into the first insulating body for electrically connecting said at least three first contacts.
In still another aspect of the present invention, an electrical connector generally comprises an insulating body formed for receiving at least three first contacts therein and for connection to another insulating body of a different connector. A shorting member is mounted on said insulating body and disposed for engaging said at least three first contacts upon insertion of said first contacts into the insulating body for electrically connecting said first contacts.
Other objects and features of the present invention will be in part apparent and in part pointed out hereinafter.